Incidence and Risk Factors of Heterotopic Ossification Following Major Elbow Trauma

Abstract

Heterotopic ossification is a common complication of Orthopaedic Trauma Association (OTA) type C distal humerus fractures and ulnohumeral fracture dislocations. The purpose of this study was to precisely define the incidence of heterotopic ossification following major elbow trauma and to identify risk factors for the development of clinically significant heterotopic ossification and for surgical excision of elbow heterotopic ossification.Current Procedural Terminology codes identified 156 patients who underwent operative intervention for a distal humerus fracture or an ulnohumeral fracture dislocation at 2 Level I trauma centers over 6 years. The incidence of elbow heterotopic ossification was recorded at >90 days following the definitive procedure. Risk factors for the development of class 3 or 4 heterotopic ossification and for surgical excision of heterotopic ossification were evaluated using separate multivariable logistic regression analyses. Brooker class 3 or 4 heterotopic ossification occurred following 18 (14%) of 125 distal humerus fractures, 15 (22%) of 69 OTA type C distal humerus fractures, and 11 (35%) of 31 ulnohumeral fracture dislocations. Surgical excision of heterotopic ossification was performed after 12 (10%) of 125 distal humerus fractures, 10 (14%) of 69 OTA type C distal humerus fractures, and 8 (26%) of 31 ulnohumeral fracture dislocations. Sustaining a severe elbow injury (P<.05) or a delay of fixation (P=.05) was found to be independent risk factors for Brooker class 3 or 4 heterotopic ossification. Severe elbow injury (P<.05) and male sex (P<.05) were associated with operative excision of heterotopic ossification.

Injury Complexity Factors Predict Heterotopic Ossification Restricting Motion After Elbow Trauma

“…The first factor, longer time from injury to surgery, has previously been shown to associate with HO after elbow trauma [3,4,6,12]. We speculate that the delay often relates to referral of more complex fractures through the office or prioritizing in multiply injured patients.…”

“…Previous studies [6,12,16], but not all [1,3], have also shown that dislocation correlates with restrictive HO. Complete ulnohumeral dislocation likely reflects greater soft tissue injury and a more severe injury, which in itself was identified as a predictor by Douglas et al [4]. Indeed, Foruria et al [6] recently showed that a prognostic model, which included injury-related factors for open fracture, elbow instability, and chest injury, was able to discriminate between patients with and without restrictive HO.…”

“…Proposed risk factors for HO after elbow trauma based on relatively small case series include head trauma [7,8], spinal cord injury [7], fracture type [1], elbow dislocation [12,16], time from injury to surgery [3,4,6,12], and severe burn [5,11,13]. Although these factors have plausible predictive capacity, it remains uncertain how much of the variation in HO is explained with clinical factors.…”

Heterotopic ossification formation after fracture-dislocations of the elbow

“…Previously, delay in treatment time between the injury and operative intervention has been noted to be related to formation of HO after these injuries. [5][6][7]13 Because many patients who develop HO require secondary surgical release or excision to regain motion and function, the development of HO can have a dramatic impact on outcome as well as the added burden of additional procedures. The ability to identify patients at risk for HO formation after elbow fracture-dislocations may be helpful in guiding treatment protocols.…”

Risk factors for decreased range of motion and poor outcomes in open periarticular elbow fractures

“…Complications following these injuries are common, with reported rates of infection ranging from 11% to 21%, neurovascular injury from 0% to 50%, nonunion from 8% to 21% [4-6], and heterotopic ossification (HO) in 0-35% [7][8][9][10][11][12][13][14][15]. Prior case series of <30 extremities have demonstrated improved outcomes and decreased complications based on the surgical approach [5] type of fixation [16], and tim\ing of surgical stabilization [5,17].…”